Answer:
2. $81
Explanation:
According to the situation the computation of weighted-average unit contribution margin is here below:-
                 Q Drive   Q Drive Plus
Selling price         $135     $180
Variable cost         $75      $90
Contribution margin
per unit              $60    $90
Sales mix             30%     70%
                    $18     $63
The weighted-average unit contribution margin = Â Q Drive + Â Q Drive Plus
= $18 + $63
= $81